Concrete-mixer.



No. 004,000. Patented nec. la', |900'. s. P. McKeLvEv.

CONCRETE MIXER.

(Applimion med Api. 9, 1900.) (No Model.) 3 Sheets-Sheet No; 604,000. f Patented 00e. I8, |000.

s. P. mcKELvEv.

CONCRETE MIIXER.

(A u t' '014A .0.1`9oo.)

(nu Model.) pp am p' a sham-sheet 2.

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no. 664,000. Patented nec, ls, |900.

S. P. McKELVEY.

coNcBETE MIXER.

`A 1 f' maA .9,1900.) (Nu Modal.) r www e p' 3 sheets-sheet a.

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UNITED STATES SAMUEL I). MOKELVEY,y

lPATENT OFFICE.

OF CHICAGO, ILLINOIS.

CONCRETE-MIXER.

SPECIFICATION forming part of Letters Patent No. 664,000, dated December 18, 1900.

Application filed April 9, 1900. Serial No. 12,244. (No model.)

and While moving through the drum is turned over repeatedly and thrown from one side of the drum toward the other until thoroughly mingled or mixed together, providing in this manner a continuous mixer or a continuous feed and discharge. By means of the defleczo tors and gravity-brackets I reduce friction and consequent Wear and tear of the machine to a minimum and require less power than is usually necessary to operate concrete-mixing machines. While the use of defiectorsin concrete-mixers is not new with me, the swinging or gravity bracket is a new and very i1n' portant element. This bracket having a pivotal support on the inner surface of the drum is mounted to swing the bracket-shelf against 3o the rising side of the drum when revolved, the concrete carried in that portion of the drum falls back on the bracket-shelf, and when the pivotal support rises in the drum to the point Where it passes under the center of 3 5 gravity the bracket falls back and discharges its load with more or less force, according to' the speed of the drum, scattering it among the deflectors in the drum, at the same time turning it over in its fall, thus providing one 4o of the essentials of good mixing. The tendency of cement or concrete to hang to the side of the drum and slide down instead of turning over with the revolution of the drum is overcome by the bracket, which, being conconcaved, checks and retains the mass against the side of the drum and at the proper elevation swings it backward, where it is caught by the defiectors and moved a step forward toward the outlet.

The objects attained are to turn over the contents of the drum repeatedly, to move thermaterial automatically and continuously from the feed to the outlet to provide a continuous mixing whilethe drum is in motion. I attain these objects by means of the device illustrated in the'accompanying drawings, in which- Figurel is an end view of a hand-power mixer and mounting. Fig. 2 is a side elevation of the mixing-drum as mounted. Fig. 3 is a side view in perspective of the drum with a portion broken away to expose the interior. Figs. 4 and 5 are longitudinal sections showing themanner of placing deflectors, looking to the right and left from the discharge end,

respectively. Fig. 6 is a transverse section of a delector. Figs. 7 and 8 are longitudinal sectional views of a modification in which the d'eflectors are dispensed with, looking to the right and left from discharge end, respectively. Fig. 9 is an end View of the same.

Similar letters and numerals refer to similar parts throughout the drawings.

In the construction of my mixer I mount a drum a horizontally on a truck or wheels I) and provide tracks l l on the outer perimeter at a suitable distance apart for the purpose required. These'tracks'carry the drum upon four friction-wheels 2 on the shafts 3, mounted in suitable bearings. Around the central .part of the drum is shown a sprocket 4, over which is carried a sprocket-chain 5, connecting the drum with a small sprocket-wheel 6, mounted at the side of the drum and operated by a crank-handle 7.

As the method of operation may be subject to change under certain conditions, as the use of steam or other motive power, spur-gears may be substituted for the sprocket and chain or any other method of propulsion suitable for the purpose, as I make no claims in this invention as to the means adopted for the purpose of revolving the drum.

The drum a has two or more series of deflectors or wings 8 secured transversely to the inner surface of the drum at an angle from a straight line longitudinally through the drum. These detlectors are secured perpendicularly to the casing of the drum, and their shape I have shown in cross-section, Fig. 6, as Haring at their free edges. This, however, is not an essential feature. They may vary in shape and length according to the size of the drum or the multiplicity of the deliectors, provided they IOO deflect the material moving between them toward the outlet 10' at one end of the drum. The position of the deflectors in the drum shows the point where the material leaves the delectors a step nearer the discharge end of the drum than where it began. Figs. 4 and 5 show the method of mounting the detlectors in the drum, having the lower point of delection nearer the outlet. Both ends of the drum are open. l0 is the feed end, and l0 is the discharge or outlet end. Both ends are flaring to provide better facilities for feeding and a more direct discharge.

In the illustration Fig. l two series of delectors are shown, each series set in a straight line through the mixing-drum. This, it will be observed, leaves two clear spaces between the series of deilectors longitudinally through the drum. Into each of these clear spaces I mount a gravity-bracket ll 011 two legs pivotally attached to the inner surface of the drum. The bracket extends longitudinally through the drum. The shelf of the bracket is more or less concavcd to increase its carrying capacity. As the drum revolves in the direction shown by the arrow the edge of the bracket-shelf lies against the inner surface of the drum. All the concrete on that side as it is carried up in the drum falls or slides back on the bracket, where it is held until the shelf is elevated to a point over the center of its pivotal support, when it falls backward, discharging its load to the bottom of the drum, scattering it more or less between the defiectors in its rear, when as the deflect-ors rise in the drum it is deflected a step nearer the outlet and is again caught by the next bracket and so continued until discharged from the drum. Wrater is introduced by means of a pipe 9.

The modification shown in Figs. 7, S, and 9 embodies the use of the gravity-brackets alone, dispensing with the deilectors. The gravity-brackets 1l do not extend throughout the drum in length, as above described, but are short and are erected having the pivotal connections with the drum at an angle relatively toastraightlinelongitudinally through the drum. This necessitates a shorter leg 12 as one of the pivotal supports of the bracket. The short legis on the end of the bracket nearer the outlet lO', causing the brackets to discharge their load constantly toward that end of the drum. These brackets are placed in series spirally around the inner surface of the drum, three or more in each series, the object desired being to permit each bracket to discharge its load in the path of the next following bracket nearer the discharge end ofthe drum. The mixing-drum constantly revolves in one direction, as shown by the arrows, and the deflectors and brackets are placed in the drum with special reference to the direction it is intended to revolve.

By either of the methods above described the concrete in the drum is in continuous motion through the drum from the moment it enters the feed end until it is discharged at the outlet, and if the feed be continuous the discharge will be the same.

The number of deiiectors or series of deiiectors and the number of gravity-brackets or series of brackets may be Varied in proportion to the size or capacity of the machine.

I am aware that changes in the form and proportion of the parts and details of construction of the devices herein shown and described as an embodiment of my invention can be made without departing from the spirit or sacrificing the advantages thereof, and I therefore reserve the right to make such changes and alterations as fairly fall within the scope of my invention.

Vhat I claim as new and novel, and desire to protect by Letters Patent, is-

l. In a mixer, a rotatable mixing-drum mounted horizontally on bearings and having the feed and outlet at opposite ends, deflectors set in series transversely against the inner surface of said mixing-drum having the points of deflection toward the outlet, a gravity-bracket mounted upon a pivotal support between the series of detlectors and longitudinally through said drum to permit the edge of said bracket to lie against the inner surface of said mixing-drum and swing' back over its pivotal support when the drum is in motion, and means for rotating said drum substantially as specified.

2. In a mixer, a rotatable mixing-drum mounted horizontally on bearings and having a feed and outlet at opposite ends, deflectors in series in parallel lines longitudinally through said mixing-drum secured transversely to the inner surface of said mixingdrum, said dellectors set at an angle with reference to a straight line longitudinally through said drum to deflect the contents toward the outlet, gravity-brackets mounted upon pivotal bearings upon the inner surface of said drum between the lines of the several series of deflectors to permit the edge of the bracket-shelf to lie against the rising inner surface of the revolving mixing-drum and swing back over its pivotal bearings when the center of gravity is passed, and means for rotating said drum substantially as described. A

3. In a mixer, a rotatable drum mounted on bearings, gravity-brackets having pivotal bearings on the inner surface of said drum to permit the edge of the bracket-shelf to lie against the side of the drum and fallback as the pivotal bearings pass the center of gravity by the rotation of said drum.

4. In a mixer, a rotatable drum mounted horizontally on bearings, gravity-brackets having pivotal bearings on the inner surface of said drum, set at an angle from a straight line longitudinally through said drum and swinging upon their bearings by the rotary motion of said drum, means for rotating said drum, substantially as specified.

5. In a gravity-bracket, a bracket-shelf, supporting-legs for said bracket-shelf, a base ICO IIO

for said supporting-legs, a pivotal connection for said supporting-legs with said base to permit said bracket to swing upon its base substantially as described. ,y

6. In a concrete-mixer, a rotatable mixingdrum mounted horizontally upon bearings having the feed at one end and the outlet at the other, short gravity-brackets mounted in series spirally through said mixing-drum upon pivotal bearings on the inner surface of said mixing-drum, each of said gravity-brackets having two supporting-legs in bearings placed at an angle relatively to a straight line longitudinally through said drum one of said supporting-legs under each bracket nearer the outlet being shorter than the other, said gravity-brackets adapted to swing upon their pivotal bearings to permit the edge ofthe Abracket-shelf to lie against the rising side of the revolving drum and fall back when the center of gravity is passed with a limited movement toward the outlet substantially as described.

7. In a mixer an open-ended mixing-drum rotatably mounted on external bearings, delectors erected in series on the inner surface of said drum to deflect the contents of said mixing-drum toward one end thereof, gravity-brackets mounted on pivotal bearings in said mixing-drum between said. series of deiiectors to swing on their bearings when the drum is in motion and means for rotating said mixing-drum substantially as speced.

8. In a mixer the combination of a mixingdrum open at both ends and rotatably mounted on external bearings with delectors erected on the inner surface of said mixing-drum in series and havingl the point of deflection toward one end thereof, gravity-brackets extending longitudinally through said mixingdrum comprising a bracket-shelf, supporting-legs for said bracket-shelf said supporting-legs being pivotally attached to the inner surface of said mixing-drum, and means for rotating said drum substantially as described.

9. In a mixer, a mixing-drum rotatably mounted on bearings, brackets pivotally mounted longitudinally on the inner surface of said mixing-drum to swing the edge of said bracket against the inner surface of said drum` and fallfbaek over its pivotal supporty 

